The invention relates to sailing craft and in particular to a system of sailor location.
The system subject of the invention may be compared by analogy with "trapeze systems" currently in use in relation to sailing craft although provides advantages to a sailor not normally attributable to a conventional "trapeze system". It is the object of the present invention to facilitate location of a sailor's body in various controlled and stable relationships to a sailing craft during all aspects of normal sailing and additionally wave jumping and "gliding".
In order that the sails of small unbalasted or lightly balasted craft sailing "close hauled" with respect to the wind may generate a horizontal forward (with respect to the craft's hull) motive force an undesirable heeling moment is generated about the fore aft axis of the hull, such force acting to capsize the vessel unless counteracted by an equal and opposite righting moment.
It has been the practice for many years to provide the equal and opposite righting moment abovementioned by utilising the weight of one or more sailors aboard the craft at points to the windward side of the fore aft axis of the craft and preferably outboard of the hull. In order that a sailor may locate his body weight at a point outboard of the crafts hull according to conventional means the sailor is provided with a harness about the wearer's torso releasably connected to a "trapeze" wire suspended from a point upon the upper regions of the mast of the craft. The length of such trapeze wire is adjusted so as to maintain the users torso above sea level with the vessel in a substantially upright position, the users feet resting upon the gunwale of the vessel and the users body almost entirely outboard of the hull.
Conventional dingy type hulls display considerable inherent "form" stability due to a relatively high beam/length ratios and such high beam/length ratio hull additionally affords a sailor the capability of placing his body weight at a considerable distance from the longitudinal centre line of the boat but not outboard of the gunwale thereby providing a considerable righting moment without utilising a trapeze system or other system designed to facilitate the placement of the sailors entire bodyweight outboard of the gunwale. Even when a trapeze system is provided with the conventional "dingy" hull having the aforementioned comparatively high beam/length ratio the trapeze system is relatively simple to master as the "form" stability of such hulls prevents capsize when an inexperienced sailor using a trapeze is a little late in swinging inboard of the the gunwale in a lull or places his bodyweight in a position on the hull other than in very close proximity to the centreline of such hull.
Board type sailing craft having low beam/length ratio hulls have recently become popular in conjunction with non-stayed masts mounted upon some type of universal joint at the junction of the mast and hull. The movable unstayed masts of such vessels are adapted to fall into non-perpendicular relationship to the hull should the sailor misjudge the necessary trim of the sail dictated by prevailing wind conditions thereby preventing what would be a capsize in a vessel with a stayed mast or mast otherwise secured in a perpendicular relationship to the hull. Such vessels as last described with moveable masts, commonly described as "sailboards", additionally permit movement of the board out of a substantially horizontal alignment with the water without necessarily altering mast and hence sail trim and this feature renders such craft forgiving in so far as placement of a sailor's body weight in respect of a hull/board having little "form" stability.
The advantages of fast manoeuvreable low beam/length ratio board type hulls are difficult to exploit in conjunction with the advantages of a conventional fixed and stayed mast rig due to the fact that, in order to counteract the heeling moment of the sail the sailor's body weight must be capable of being placed outboard of the gunwale thereby dictating some type of trapeze system.
Trapeze systems presently available provide no location or hand holds for the trapeze user whilst outboard of the hull except in so far as such systems prevent movement of the trapeze user into an area defined by the outside of an arc subtended about the point of attachment of the trapeze wire to the mast by a straight line equal to the length of the trapeze wire. In short conventional trapeze systems do not provide an infinite variety of handholds to the user whilst outboard of the hull and furthermore provide no location for the user in respect of movement in an upwards or inwards direction relative to the gunwale on the trapezer's side of the hull. The aforementioned defect of presently existing wire trapeze systems making learning to sail low beam/length ratio board type hulled craft with fixed masts displaying the aforementioned lack of form stability extremely difficult, particularly for beginners as for example in choppy waters a person trapezing outboard of the gunwale of such craft is often thrown upwards and/or inwards with respect to the gunwale on the user's side of the craft.
After a sailor has "tacked" when utilising a conventional trapeze system there is a period of instability when assuming the correct position upon the new windward side of the craft as the degree of righting moment required of the sailor changes rapidly from nil, when the boat is head to wind to a considerable degree when the craft has once again gained speed and is correctly trimmed on the new tack. The degree of righting moment required at any instant during the lastmentioned tacking process may change rapidly with the alteration of sail trim and is not necessarily progressive. This requires a trapezer to vary his position with respect to the longitudinal centre line of the boat quickly and a number of times whilst setting the boat up on the new tack. The lastmentioned adjustments to trapezing position must be accomplished whilst the sailor is attaching himself to the new windward side trapeze system and furthermore whilst manipulating controls. Conventional trapeze systems are not well adapted to serve the sailor in such conditions as they are difficult to "hook into" due to the flexible nature of "wire" systems which often require two hands to ensure connection of the wire system to the trapeze harness hook and furthermore due to the fact that manipulation of one segment of a wire does not result in accurate control of another section of such wire. Wires additionally do not provide an infinite variety of convenient hand holds due to their extremely small diameter.